Hearing aid devices are used to enhance or improve the quality of life for the user. These devices may amplify certain sounds that have been unheard to some degree by the user in the past. Because each user of a hearing aid has varying degrees of hearing loss, these devices are programmable for adaptation to the user's needs.
In order to program a hearing aid to be tailored to the user's hearing needs, the user's hearing threshold may be measured using a sound-stimulus-producing device and calibrated headphone. The measurement of the hearing threshold may take place in a sound-isolating room. For example, the measurement may occur in a room where there is very little audible noise. The sound-stimulus-producing device and the calibrated headphones may be referred to as an audiometer.
The audiometer may generate pure tones at various frequencies between 125 Hz and 12,000 Hz that are representative of the frequency bands in which the tones are included. These tones may be transmitted through the headphones of the audiometer to the individual being tested. The intensity or volume of the pure tones is varied until the individual can just barely detect the presence of the tone. For each pure tone, the intensity of the tone at which the individual can just barely detect the presence of the tone is known as the individual's air conduction threshold of hearing. The collection of the thresholds of hearing at each of the various pure tone frequencies is known as an audiogram and may be presented in graphical form.
When the threshold of hearing in each frequency band has been determined, this threshold may be used to estimate the amount of amplification, compression, and other adjustment that will be employed in the hearing aid device to compensate for the individual's loss of hearing. Further, users of hearing aids continue to demand that the size of the hearing aids decrease. In addition, users may desire to have an aesthetically pleasing hearing aid device.